Bioinspired Multifunctional Anti-icing Hydrogel

The recent anti-icing strategies in the state of the art mainly focused on three aspects: inhibiting ice nucleation, preventing ice propagation, and decreasing ice adhesion strength. However, it is has proved difficult to prevent ice nucleation and propagation while decreasing adhesion simultaneously, due to their highly distinct, even contradictory design principles. In nature, anti-freeze proteins (AFPs) offer a prime example of multifunctional integrated anti-icing materials that excel in all three key aspects of the anti-icing process simultaneously by tuning the structures and dynamics of interfacial water. Here, inspired by biological AFPs, we successfully created a multifunctional anti-icing material based on polydimethylsiloxane-grafted polyelectrolyte hydrogel that can tackle all three aspects of the anti-icing process simultaneously. The simplicity, mechanical durability, and versatility of these smooth hydrogel surfaces make it a promising option for a wide range of anti-icing applications

Technical evaluation report, AGARD Fluid Dynamics Panel Symposium on Effects of Adverse Weather on Aerodynamics

The purpose of the meeting on Effects of Adverse Weather on Aerodynamics was to provide an update of the stae-of-the-art with respect to the prediction, simulation, and measurement of the effects of icing, anti-icing fluids, and various precipitation on the aerodynamic characteristics of flight vehicles. Sessions were devoted to introductory and survey papers and icing certification issues, to analytical and experimental simulation of ice frost contamination and its effects of aerodynamics, and to the effects of heavy rain and deicing/anti-icing fluids

Numerical modeling of runback water on ice protected aircraft surfaces

A numerical simulation for 'running wet' aircraft anti-icing systems is developed. The model includes breakup of the water film, which exists in regions of direct impingement, into individual rivulets. The wetness factor distribution resulting from the film breakup and the rivulet configuration on the surface are predicted in the numerical solution procedure. The solid wall is modeled as a multilayer structure and the anti-icing system used is of the thermal type utilizing hot air and/or electrical heating elements embedded with the layers. Details of the calculation procedure and the methods used are presented

Effects of anisotropic composite skin on electrothermal anti-icing system

To study the effects of anisotropic thermal conductivity of composite aircraft skin on the heat transfer characteristics of electrothermal anti-icing system, the differential equation of anisotropic heat conduction was established using coordinate transformation of principal anisotropy axis. In addition, it was coupled with the heat and mass transfer model of the runback water film on the anti-icing surface to perform numerical simulation of the electrothermal anti-icing system. The temperature results of the vertical and cylindrical orthotropic thermal conduction in the rectangular and semi-cylindrical composite skin were consistent with those obtained by the traditional orthotropic model, which verified the anisotropic heat conduction model. The temperature distribution of anti-icing surface agreed well with the literature data, which validated the coupled heat and mass model of the runback water flow and the anisotropic skin. The anisotropic thermal conductivity of composite skin would make temperature change more gradual, and the effect was more significant where the curvature of the temperature curve was greater. However, the anti-icing surface of the electrothermal anti-icing system was slightly affected by the anisotropic heat conduction of the multilayered composite skin

Evaluation of Anti-Icing/De-Icing Products Under Controlled Environmental Conditions

Snow and ice removal are important tasks during the winter season and large amounts of anti-icing and de-icing chemicals are used and there is a critical need to review and synthesize information from the literature to compare and contrast anti-icing and de-icing chemicals to understand their environmental impact and support decision making. The effectiveness, costs, and environmental impact of commonly used and alternative anti-icing and de-icing chemicals were reviewed in this study. Application of anti-icing and de-icing chemicals may increase ion concentrations in soils and change nitrogen cycle, soil pH, and trace metal concentrations, affect surface water and groundwater, and increase public health risks. Life cycle assessment was conducted to quantitively evaluate environmental impact of selected anti-icing and de-icing chemicals. A decision support tool on environmental impact was developed to evaluate environmental impact of anti-icing and de-icing chemicals in ten different environmental impact categories. The results showed the environmental life cycle assessment tool developed in this study can be used to compare multiple environment impacts to support decision making for winter operation chemicals

Mechanically robust transparent anti-icing coatings: Roles of dispersion status of Titanate nanotubes

© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Ice accretion on automobiles, aerospace components, precision instruments, and photovoltaic devices detrimentally affect their performance and increase the maintenance cost. Despite significant efforts devoted to the investigation of anti-icing coatings in the past decades, mechanically robust and transparent anti-icing coatings are rarely reported. In this study, titanate nanotubes are used as filler to prepare mechanically robust anti-icing coatings with a sol-gel method. Specially, the effect of dispersion status of nanotubes on the transmittance, surface roughness, and water repellency is investigated. The optimized smooth, transparent coating exhibits higher water repellency and better anti-icing performance in terms of ice-adhesion strength, icing delay time, and ice-nucleation temperature than the rough one. Much higher hardness and scratch resistance than that of commercially available icephobic or anti-icing coatings is obtained on the smooth, transparent sample; the coating also presents good adhesion to the substrate

Numerical Modeling of Anti-icing Systems and Comparison to Test Results on a NACA 0012 Airfoil

A series of experimental tests were conducted in the NASA Lewis IRT on an electro-thermally heated NACA 0012 airfoil. Quantitative comparisons between the experimental results and those predicted by a computer simulation code were made to assess the validity of a recently developed anti-icing model. An infrared camera was utilized to scan the instantaneous temperature contours of the skin surface. Despite some experimental difficulties, good agreement between the numerical predictions and the experiment results were generally obtained for the surface temperature and the possibility for each runback to freeze. Some recommendations were given for an efficient operation of a thermal anti-icing system

Anti-icing coatings and methods

A method of inhibiting or preventing bonding between snow or ice and a substrate. The method includes applying an adhesive to the substrate, broadcasting an aggregate onto the adhesive, the aggregate having the capacity to receive an anti-icing chemical into the aggregate, and applying the anti-icing chemical onto the aggregate so that at least a portion of the anti-icing chemical is received into at least a portion of the aggregate.https://digitalcommons.mtu.edu/patents/1112/thumbnail.jp

Research Progress of Superhydrophobic Materials in the Field of Anti-/De-Icing and Their Preparation: A Review

Accumulated ice has brought much damage to engineering and people’s lives. The accumulation of ice can affect the flight safety of aircraft and lead to the failure of cables and power generation blades; it can even cause damage to human life. Traditional anti-icing and de-icing strategies have many disadvantages such as high energy consumption, low efficiency, or pollution of the environment. Therefore, inspired by animal communities, researchers have developed new passive anti-icing materials such as superhydrophobic material. In this paper, the solid surface wetting phenomenon and superhydrophobic anti-icing and de-icing mechanism were introduced. The methods of fabrication of superhydrophobic surfaces were summarized. The research progress of wear-resistant superhydrophobic coatings, self-healing/self-repairing superhydrophobic coatings, photothermal superhydrophobic coatings, and electrothermal superhydrophobic coatings in the field of anti-icing and de-icing was reviewed. The current problems and challenges were analyzed, and the development trend of superhydrophobic materials was also prospected in the field of anti-icing and de-icing. The practicality of current superhydrophobic materials should continue to be explored in depth

Establishing an Anti- Icing Program

Establishing an Anti-Icing Program in the City of Mishawaka, Indiana—In this session we go through the City of Mishawaka’s process of establishing an effective anti-icing program over the course of 14 years